An efficient and rapid Agrobacterium tumefaciens-mediated transformation protocol was developed to generate activation-tagged mutant lines with the aim of large-scale functional analysis of the potato genome. The expl...An efficient and rapid Agrobacterium tumefaciens-mediated transformation protocol was developed to generate activation-tagged mutant lines with the aim of large-scale functional analysis of the potato genome. The explants were inoculated with an Agrobacterium strain harboring the binary plasmid pSKI074 containing four CaMV 35S enhancers in the T-DNA region which activates the downstream genes in the host plant after its integration. Various parameters investigated to increase transformation efficiency were the type and age of explant, cultivar, hormone combinations, preculture of explants, period of co-cultivation with bacteria and concentration of bacterial cultures used for transformation. Stem explants from 5 week old plantlets of cv. Bintje which had undergone phytohormone pretreatment for 4 days, inoculation with diluted bacterial concentration of OD600 = 0.2 containing acetosyringone followed by 2 days of co-cultivation and selection in media with IAA and trans-zeatin all helped in greatly improving the transformation efficiency. The total time required from infection to rooted shoots was 6-7 weeks. Initial evidence for stable integration and expression of the transgenes by PCR analysis showed that over 93% of the regenerated lines were transgenic and this was confirmed by Southern hybridization.展开更多
在新型电力系统复杂工况下,以策略表为主体、通过“离线仿真、在线匹配”的预案式频率稳定控制方案存在较高失配风险,甚至因调控失当引发二次冲击,严重威胁电力系统的安全稳定运行。提出一种计及预案式失配冲击的响应驱动频率稳定紧急...在新型电力系统复杂工况下,以策略表为主体、通过“离线仿真、在线匹配”的预案式频率稳定控制方案存在较高失配风险,甚至因调控失当引发二次冲击,严重威胁电力系统的安全稳定运行。提出一种计及预案式失配冲击的响应驱动频率稳定紧急切负荷策略。该策略动作在预案式控制之后,是对预案式控制的有益补充,能够有效提升系统频率稳定性。首先建立了基于系统频率响应(system frequency response,SFR)模型辨识的频率稳定切负荷量计算方法。提出了基于频率稀疏量测的SFR模型辨识方法,在此基础上建立了含稳定控制的SFR模型,根据频率稳定控制目标迭代求解切负荷量。其次,建立了基于Transformer网络的频率控制敏感点挖掘模型,通过分析关键发电机母线节点频率时序值和频率控制敏感点的映射关系,实现响应驱动的频率控制敏感点在线挖掘。最后,按照敏感点排序快速分配控制措施总量,构建频率稳定紧急控制方案。在某实际交直流混联万节点仿真系统验证了所提方法的有效性。展开更多
文摘An efficient and rapid Agrobacterium tumefaciens-mediated transformation protocol was developed to generate activation-tagged mutant lines with the aim of large-scale functional analysis of the potato genome. The explants were inoculated with an Agrobacterium strain harboring the binary plasmid pSKI074 containing four CaMV 35S enhancers in the T-DNA region which activates the downstream genes in the host plant after its integration. Various parameters investigated to increase transformation efficiency were the type and age of explant, cultivar, hormone combinations, preculture of explants, period of co-cultivation with bacteria and concentration of bacterial cultures used for transformation. Stem explants from 5 week old plantlets of cv. Bintje which had undergone phytohormone pretreatment for 4 days, inoculation with diluted bacterial concentration of OD600 = 0.2 containing acetosyringone followed by 2 days of co-cultivation and selection in media with IAA and trans-zeatin all helped in greatly improving the transformation efficiency. The total time required from infection to rooted shoots was 6-7 weeks. Initial evidence for stable integration and expression of the transgenes by PCR analysis showed that over 93% of the regenerated lines were transgenic and this was confirmed by Southern hybridization.
文摘在新型电力系统复杂工况下,以策略表为主体、通过“离线仿真、在线匹配”的预案式频率稳定控制方案存在较高失配风险,甚至因调控失当引发二次冲击,严重威胁电力系统的安全稳定运行。提出一种计及预案式失配冲击的响应驱动频率稳定紧急切负荷策略。该策略动作在预案式控制之后,是对预案式控制的有益补充,能够有效提升系统频率稳定性。首先建立了基于系统频率响应(system frequency response,SFR)模型辨识的频率稳定切负荷量计算方法。提出了基于频率稀疏量测的SFR模型辨识方法,在此基础上建立了含稳定控制的SFR模型,根据频率稳定控制目标迭代求解切负荷量。其次,建立了基于Transformer网络的频率控制敏感点挖掘模型,通过分析关键发电机母线节点频率时序值和频率控制敏感点的映射关系,实现响应驱动的频率控制敏感点在线挖掘。最后,按照敏感点排序快速分配控制措施总量,构建频率稳定紧急控制方案。在某实际交直流混联万节点仿真系统验证了所提方法的有效性。
文摘由于不同井间工况差异显著,异常振动特征分布存在跨井不一致性,传统基于单井数据的监测方法难以适应跨井场景。为此,以黏滑振动为例,对不同工况下的黏滑振动数据特征进行了对比分析,提出了一种结合深度判别迁移学习网络(domain adaptive transfer learning network,DDTLN)与BO⁃Transformer⁃LSTM的跨井异常振动识别方法。将近钻头振动数据输入到DDTLN模型中,通过卷积层与改进的联合分布自适应(IJDA)机制减小域间特征差异,实现跨域特征提取;将提取的特征输入到BO⁃Transformer⁃LSTM模型中挖掘时序信息,实现跨井高效分类。试验结果表明:不同工况下井间振动信号差异显著,传统方法跨域分类效果较差;经过DDTLN处理后,不同域间的数据特征有了很好的对齐,跨域识别准确率高达91.5%;DDTLN⁃BO⁃Transformer⁃LSTM模型能够有效解决跨井识别问题,分类准确率最高达96.7%,显著优于传统单井识别方法,具有更好的泛化能力。该研究可为跨井场景下的井下异常振动识别提供新思路。